WEDNESDAY, April 21 (HealthDay News) -- Self-esteem increases as people grow older, but dips when people are in their 60s, although those who make more money and are healthier tend to retain better views of themselves, researchers have found.

In the study, published in the April issue of the Journal of Personality and Social Psychology, researchers surveyed 3,617 U.S. adults aged 25 to 104, trying to reach all of them four times between 1986 and 2002.

"Self-esteem is related to better health, less criminal behavior, lower levels of depression and, overall, greater success in life," the study's lead author, Ulrich Orth, said in a news release from the American Psychological Association. "Therefore, it's important to learn more about how the average person's self-esteem changes over time."

Young people had the lowest self-esteem, but it grew as people aged, peaking at about age 60. Women had lower self-esteem than men, on average, until they reached their 80s and 90s, the study authors found.

Wealth and health played major roles in boosting self-esteem, especially in older people. "Specifically, we found that people who have higher incomes and better health in later life tend to maintain their self-esteem as they age," Orth said. "We cannot know for certain that more wealth and better health directly lead to higher self-esteem, but it does appear to be linked in some way. For example, it is possible that wealth and health are related to feeling more independent and better able to contribute to one's family and society, which in turn bolsters self-esteem."

As to why self-esteem peaks in middle-age and then often drops as people get older, the researchers suggested several theories.

"Midlife is a time of highly stable work, family and romantic relationships. People increasingly occupy positions of power and status, which might promote feelings of self-esteem," study co-author Richard Robins, of the University of California at Davis, said in the news release. "In contrast, older adults may be experiencing a change in roles such as an empty nest, retirement and obsolete work skills in addition to declining health."